Off-shore oil drilling apparatus



Jan. 19, 1965 M. R. ELLIOTT 3,165,898

OFF-SHORE OIL DRILLING APPARATUS Filed June 11, 1962 3 Sheets-Sheet 1 INVENTOI? Melvin R. Elliott M. R. ELLIOTT OFF-SHORE OIL DRILLING APPARATUS Jan. 19, 1965 3 Sheets-Sheet 2 Filed June 11 1962 R w M W Jan. 19, 1965 M. R. ELLIOTT OFF-SHORE OIL DRILLING APPARATUS Filed June 11 1962 5 Sheets-Sheet 5 United States Patent 3,165,898 OFF-SHGRE OIL DRHILING APPARATUS Melvin R. Elliott, Lake Charles, Flap, assignor to Continental Gil Company, Ponca City, Okla, a corporation of Delaware Filed June 11, 1962, Ser. No. 291,681 3 Claims. (Ql. 61-465) This invention relates to an apparatus for drilling wells beneath the surface of a body of water.

Drilling off-shore oil wells has always been a difficult and expensive operation. Usually there is involved suitable apparatus for positioning the required drilling equipment at a safe level above the surface of the waters in which the drilling operations are being conducted. Heretofore, various types of apparatus have been proposed for use in off-shore drilling operations, and they have generally fallen into two main classes:

(1) Fixed platforms positioned on piling which is driven into the ocean floor and (2) Floatable drilling barges which are generally submersible and can be sunk onto the ocean floor at the drilling location.

Drilling platforms positioned on piling reaching down into the ocean floor are very expensive and cannot be readily recovered after the completion of the drilling operations. Submersible drilling barges while they may be moved from one location to another, are extremely expensive to build and maintain. The ideal drilling barge should have a hull or pontoon sufficient in size to impart stability to the barge either when the barge is being floated to the drilling site or after it has been sunk to the ocean floor at the site. It is also important that the hull or pontoon be no higher than necessary so as to reduce the area against which wind and ocean waves or currents would act to move the submersible drilling barge.

It is among the objects of the present invention to provide a relatively inexpensive and durable off-shore oil drilling apparatus which is efficient in operation but which eliminates many of the disadvantages of the prior art apparatus referred to hereinbefore.

Another object is to provide an apparatus of the class described which may be efficiently moved from one location to another.

The foregoing and other objects and advantages of the invention will become apparent upon full consideration of the following detailed description and accompanying drawings, in which FIGURE 1 is a sectional elevation illustrating an apparatus which embodies the teachings of the present invention;

FIGURE 2 is a of FIGURE 1;

FIGURE 3 is a sectional view taken on the line of FIGURE 2, and

PlGURES 4 and 5 are views, partly in section, which illustrate details that will be specifically referred to hereinafter.

Referring more particularly to the drawings, the numeral 2 generally designates an elongate cylindrical column which is adapted to extend along the surface of the body of water. A tubular sleeve 3 is concentrically disposed in the elongate cylindrical column 2 and may, if desired, extend further downwardly, as indicated in FIG- URE 1.

Between the column 2 and the its concentric inner tubular sleeve 3 there is a plurality of transverse, i.e. horizontal, partitions 5, thereby forming a series of superposed compartments 7.

A flared or frusto-conical skirt connects with the exterior of the cylindrical column at a position which is sectional view taken on the line 22 tically extending above the centerline of the latter, and it extends downwardly for a substantial distance below the bottom of the said cylindrical column as shown.

A plurality of horizontal partitions 12 extend between the exterior of the cylindrical column 2 and the divergently depending skirt 1t) and form a series of superposed compartments 13.

The lowermost end of the flared or frusto-conical skirt 10 connects with an upwardly and divergently extending inner wall 15 which terminates below the lowermost of the horizontal partitions 12 and is connected thereto by a vertical wall 18.

Transverse partitions 20 connect the flared skirt 10 with its upwardly and divergently etxending wall 15, thereby providing a series of compartments 25. According to the immediately foregoing construction and arrangement three series of compartments are formed, i.e. 7, 13 and 25.

According to a preferred embodiment the outside diameter of the bottom of the flared skirt 10 may be six times the outside diameter of the column 2.

A platform 30 is mounted atop the column 2 (and its concentric inner wall 3), and, if desired, this platform may be provided with a center drill opening as indicated by the dotted lines 35 in FIGURE 2.

Alternately, the spaces between the exterior of the tubular sleeve 3 and the exterior of the frusto-conical skirt 10 may be traversed by a pair of spaced parallel verportions 40 which provide access space therebetween for the drilling of a row of apertures 41 for a purpose to be later described.

Each of the compartments 7, 13 and 25 is provided with a vent 42 by means of which it may be filled or emptied of water.

A pipe 44 communicates with each of the compartments through the aforementioned apertures 41 and with the aid of suitable compressed air lines, etc., the various compartments may be evacuated.

In order to move the apparatus of the invention to a desired location, all or most of the compartments 7, 13 and 25 are emptied by compressed air, as previously described. Being symmetrical, the structure may, by proper emptying of some compartments and ballasting of others, be made to float on an even keel. After the apparatus has been float to the desired location, the vents 42 of the evacuated compartments are opened, thereby permitting water to displace the air in all of the previously emptied compartments to a level which corresponds to the level of the outside water.

The column 2 and flared skirt ltl (or frusto-conical base) and their inner walls and intermediate partitions may all be constructed of any conventional material having suflicient structural strength, such as steel. However, concrete provides the advantages of economy, lightness in Weight, and comparative immunity to corrosion and electrolysis by sea water.

One of the latest developments in off-shore production is to install the permanent well head equipment, including piping connections, on the bottom of the body of water where it will be out of reach of the elements. The present invention lends itself ideally to this technique, the interior of the frusto-conical base providing ample working space at the bottom in the manner of a very large diving bell, after the Water has been removed therefrom.

While I have shown and described certain specific embodiments of the present invention, it will be readily understood that I do not wish to be limited exactly thereto, since various modifications may be made without departing from the scope of the invention as defined in the appended claims.

What I claim is:

1. Apparatus for drilling into earth formations at the bottom of a body of water comprising, in combination, a cylindrical column; a tubular sleeve concentrically disposed in said cylindrical column; a frusto-conical skirt connected to the exterior of said cylindrical column above its horizontal center line and extending downwardly for a substantial distance below the bottom thereof whereby the base of the skirt has a diameter substantially in excess of that of the cylindrical column; transverse partitions connecting the exterior of said cylindrical column and the interior of said frusto-conical skirt and defining water-tight compartments therebetween; an inner wall member connected to said frusto-eonical skirt adjacent the bottom thereof and extending upwardly and divergently with respect thereto; transverse partitions connecting said frusto-conical skirt and said inner wall member and defining Water-tightcompartments therebetween; a platform atop said cyindrical column; means for flooding each of said compartments with water; and means for evacuating said compartments.

2. Apparatus for drilling into earth formations at the bottom of a body of water comprising, in combination, a cylindrical column; a tubular sleeve concentrically disposed in said cylindrical column; transverse partitions connecting said tubular sleeve and said cylindrical column and defining water-tight compartments therebetween; a frusto-conical skirt connected to the exterior of said cylindrical column above its horizontal center line and extend ing downwardly for a substantial distance below the bottom thereof whereby the base of the skirt has a diameter substantially in excess of that of the cylindrical column; an inner wall member connected to said frustoconical skirt adjacent thebottom thereof and extending upwardly and divergently with respect thereto; transverse partitions connecting said frusto-conical skirt and said inner wall and defining water-tight compartments therebetween; a platform atop said cylindrical column; means for flooding each of said compartments with water; and means for evacuating said compartments.

3. Apparatus for drilling into earth formations at the bottom of a body of water comprising, in combination, a cylindrical column; a tubular sleeve concentrically disposed in said cylindrical column; transverse partitions connecting said tubular sleeve and said cylindrical column and defining water-tight compartments therebetween; a frusto-conical skirt connected to the exterior of said cylindrical column above its horizontal center line and extending downwardly for a substantial distance below the bottom thereof whereby the base of the skirt has a diameter substantially in excess of that of the cylindrical column; an inner wall member connected to said frustoconical skirt adjacent the bottom thereof and extending upwardly and divergently with respect thereto; transverse partitions connecting said frusto-conical skirt and said inner wall and defining compartments therebetween; a vent valve for each of said water-tight compartments; and a compressed air line extending into each of said References Cited in the file of this patent UNITED STATES PATENTS 2,187,871 Voorhees Jan. 23, 1940 2,622,404 Rice Dec. 23, 1952 2,669,846 Shannon Feb. 23, 1954 2,677,935 Schaufele May 11, 1954 2,857,744 Swiger Oct. 28, 1958 2,940,266 Smith June 14, 1960 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,165,898 January 19, 1965 Melvin R. Elliott It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below Y Column 4, line 24, for "of said" read of said compartments.

Signed and sealed this 22nd day of June 1965.

(SEAL) Attest:

ERNEST w. SWIDER EDWARD J. BRENNER Aitesting Officer Commissioner of Patents 

1. APPARATUS FOR DRILLING INTO EARTH FORMATION AT THE BOTTOM OF A BODY OF WATER COMPRISING, IN COMBINATION, A CYLINDRICAL COLUMN; A TUBULAR SLEEVE CONCENTRICALLY DISPOSED IN SAID CYLINDRICAL COLUMN; A FRUSTO-CONICAL SKIRT CONNECTED TO THE EXTERIOR OF SAID CYLINDRICAL COLUMN ABOVE ITS HORIZONTAL CENTER LINE AND EXTENDING DOWNWARDLY FOR A SUBSTANTIAL DISTANCE BELOW THE BOTTOM THEREOF WHEREBY THE BASE OF THE SKIRT HAS A DIAMETER SUBSTANTIALLY IN EXCESS OF THAT OF THE CYLINDER COLUMN; TRANSVERSE PARTITIONS CONNECTING THE EXTERIOR OF SAID CYLINDRICAL COLUMN AND THE INTERIOR OF SAID FRUSTO-CONICAL SKIRT AND DEFINING WATER-TIGHT COMPARTMENTS THEREBETWEEN; AN INNER WALL MEMBER CONNECTED TO SAID FRUSTO-CONICAL SKIRT ADJACENT THE BOTTOM THEREOF AND EXTENDING UPWARDLY AND DIVERGENTLY WITH RESPECT THERETO; TRANSVERSE PARTITIONS CONNECTING SAID FRUSTO-CONICAL SKIRT AND SAID INNER WALL MEMBER AND DEFINING WATER-TIGHT COMPARTMENTS THEREBETWEEN; A PLATFORM ATOP SAID CYLINDRICAL COLUMN; MEANS FOR FLOODING EACH OF SAID COMPARTMENTS WITH WATER; AND MEANS FOR EVACUATING SAID COMPARTMENTS. 